From 06b4e09aab6c1ae6b3991a729d2fcb31e358e7f3 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 11 Oct 2022 13:01:11 -0700 Subject: [PATCH] pstore/ram: Set freed addresses to NULL For good measure, set all the freed addresses to NULL when managing przs. Cc: Anton Vorontsov Cc: Colin Cross Cc: Tony Luck Signed-off-by: Kees Cook Reviewed-and-tested-by: Guilherme G. Piccoli Link: https://lore.kernel.org/r/20221011200112.731334-5-keescook@chromium.org --- fs/pstore/ram.c | 13 ++++++++----- fs/pstore/ram_core.c | 11 +++++++++-- fs/pstore/ram_internal.h | 2 +- 3 files changed, 18 insertions(+), 8 deletions(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index f5bf360..5a39fa8 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -453,25 +453,27 @@ static void ramoops_free_przs(struct ramoops_context *cxt) int i; /* Free pmsg PRZ */ - persistent_ram_free(cxt->mprz); + persistent_ram_free(&cxt->mprz); /* Free console PRZ */ - persistent_ram_free(cxt->cprz); + persistent_ram_free(&cxt->cprz); /* Free dump PRZs */ if (cxt->dprzs) { for (i = 0; i < cxt->max_dump_cnt; i++) - persistent_ram_free(cxt->dprzs[i]); + persistent_ram_free(&cxt->dprzs[i]); kfree(cxt->dprzs); + cxt->dprzs = NULL; cxt->max_dump_cnt = 0; } /* Free ftrace PRZs */ if (cxt->fprzs) { for (i = 0; i < cxt->max_ftrace_cnt; i++) - persistent_ram_free(cxt->fprzs[i]); + persistent_ram_free(&cxt->fprzs[i]); kfree(cxt->fprzs); + cxt->fprzs = NULL; cxt->max_ftrace_cnt = 0; } } @@ -555,9 +557,10 @@ static int ramoops_init_przs(const char *name, while (i > 0) { i--; - persistent_ram_free(prz_ar[i]); + persistent_ram_free(&prz_ar[i]); } kfree(prz_ar); + prz_ar = NULL; goto fail; } *paddr += zone_sz; diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 9e1047f..97dde52 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -544,8 +544,14 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, return 0; } -void persistent_ram_free(struct persistent_ram_zone *prz) +void persistent_ram_free(struct persistent_ram_zone **_prz) { + struct persistent_ram_zone *prz; + + if (!_prz) + return; + + prz = *_prz; if (!prz) return; @@ -569,6 +575,7 @@ void persistent_ram_free(struct persistent_ram_zone *prz) persistent_ram_free_old(prz); kfree(prz->label); kfree(prz); + *_prz = NULL; } struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, @@ -605,6 +612,6 @@ struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, return prz; err: - persistent_ram_free(prz); + persistent_ram_free(&prz); return ERR_PTR(ret); } diff --git a/fs/pstore/ram_internal.h b/fs/pstore/ram_internal.h index 440ee7a..5f69469 100644 --- a/fs/pstore/ram_internal.h +++ b/fs/pstore/ram_internal.h @@ -82,7 +82,7 @@ struct persistent_ram_zone { struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, u32 sig, struct persistent_ram_ecc_info *ecc_info, unsigned int memtype, u32 flags, char *label); -void persistent_ram_free(struct persistent_ram_zone *prz); +void persistent_ram_free(struct persistent_ram_zone **_prz); void persistent_ram_zap(struct persistent_ram_zone *prz); int persistent_ram_write(struct persistent_ram_zone *prz, const void *s, -- 2.7.4